SAM7S128_14 Datasheet, PDF (535/775 Pages) ATMEL Corporation – ARM-based Flash MCU

35.6.12 UDP Transceiver Control Register
Register Name:
UDP_ TXVC
Access Type:
Read-write
31
30
29
28
27
26
25
24
–
–
–
–
–
–
–
–
23
22
21
20
19
18
17
16
–
–
–
–
–
–
–
–
15
14
13
12
11
10
–
–
–
–
–
–
9
8
–
TXVDIS
7
6
5
4
3
2
1
0
–
–
–
–
–
–
–
–
WARNING: The UDP peripheral clock in the Power Management Controller (PMC) must be enabled before any read/write
operations to the UDP registers including the UDP_TXCV register.
• TXVDIS: Transceiver Disable
When UDP is disabled, power consumption can be reduced significantly by disabling the embedded transceiver. This can
be done by setting TXVDIS field.
To enable the transceiver, TXVDIS must be cleared.
NOTE: If the USB pullup is not connected on DP, the user should not write in any UDP register other than the UDP_ TXVC
register. This is because if DP and DM are floating at 0, or pulled down, then SE0 is received by the device with the conse-
quence of a USB Reset.
SAM7S Series [DATASHEET]
6175M–ATARM–26-Oct-12
535